/*
 * Copyright (c) 2007, 2021, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */
/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.sun.org.apache.xml.internal.utils;

import java.util.StringTokenizer;
import java.util.Vector;

import javax.xml.transform.Source;
import javax.xml.transform.TransformerException;
import javax.xml.transform.URIResolver;
import javax.xml.transform.sax.SAXSource;

import com.sun.org.apache.xml.internal.utils.SystemIDResolver;

import org.xml.sax.Attributes;
import org.xml.sax.InputSource;
import org.xml.sax.helpers.DefaultHandler;

/**
 * Search for the xml-stylesheet processing instructions in an XML document.
 *
 * @see <a href="http://www.w3.org/TR/xml-stylesheet/">Associating Style Sheets with XML documents, Version 1.0</a>
 */
public class StylesheetPIHandler extends DefaultHandler {
    /**
     * The baseID of the document being processed.
     */
    String m_baseID;

    /**
     * The desired media criteria.
     */
    String m_media;

    /**
     * The desired title criteria.
     */
    String m_title;

    /**
     * The desired character set criteria.
     */
    String m_charset;

    /**
     * A list of SAXSource objects that match the criteria.
     */
    Vector m_stylesheets = new Vector();

    // Add code to use a URIResolver. Patch from Dmitri Ilyin.

    /**
     * The object that implements the URIResolver interface,
     * or null.
     */
    URIResolver m_uriResolver;

    /**
     * Get the object that will be used to resolve URIs in href
     * in xml-stylesheet processing instruction.
     *
     * @param resolver An object that implements the URIResolver interface,
     *                 or null.
     */
    public void setURIResolver(URIResolver resolver) {
        m_uriResolver = resolver;
    }

    /**
     * Get the object that will be used to resolve URIs in href
     * in xml-stylesheet processing instruction.
     *
     * @return The URIResolver that was set with setURIResolver.
     */
    public URIResolver getURIResolver() {
        return m_uriResolver;
    }

    /**
     * Construct a StylesheetPIHandler instance that will search
     * for xml-stylesheet PIs based on the given criteria.
     *
     * @param baseID  The base ID of the XML document, needed to resolve
     *                relative IDs.
     * @param media   The desired media criteria.
     * @param title   The desired title criteria.
     * @param charset The desired character set criteria.
     */
    public StylesheetPIHandler(String baseID, String media, String title,
                               String charset) {

        m_baseID = baseID;
        m_media = media;
        m_title = title;
        m_charset = charset;
    }

    /**
     * Return the last stylesheet found that match the constraints.
     *
     * @return Source object that references the last stylesheet reference
     * that matches the constraints.
     */
    public Source getAssociatedStylesheet() {

        int sz = m_stylesheets.size();

        if (sz > 0) {
            Source source = (Source) m_stylesheets.elementAt(sz - 1);
            return source;
        } else
            return null;
    }

    /**
     * Handle the xml-stylesheet processing instruction.
     *
     * @param target The processing instruction target.
     * @param data   The processing instruction data, or null if
     *               none is supplied.
     * @throws org.xml.sax.SAXException Any SAX exception, possibly
     *                                  wrapping another exception.
     * @see org.xml.sax.ContentHandler#processingInstruction
     * @see <a href="http://www.w3.org/TR/xml-stylesheet/">Associating Style Sheets with XML documents, Version 1.0</a>
     */
    public void processingInstruction(String target, String data)
            throws org.xml.sax.SAXException {

        if (target.equals("xml-stylesheet")) {
            String href = null;  // CDATA #REQUIRED
            String type = null;  // CDATA #REQUIRED
            String title = null;  // CDATA #IMPLIED
            String media = null;  // CDATA #IMPLIED
            String charset = null;  // CDATA #IMPLIED
            boolean alternate = false;  // (yes|no) "no"
            StringTokenizer tokenizer = new StringTokenizer(data, " \t=\n", true);
            boolean lookedAhead = false;
            Source source = null;

            String token = "";
            while (tokenizer.hasMoreTokens()) {
                if (!lookedAhead)
                    token = tokenizer.nextToken();
                else
                    lookedAhead = false;
                if (tokenizer.hasMoreTokens() &&
                        (token.equals(" ") || token.equals("\t") || token.equals("=")))
                    continue;

                String name = token;
                if (name.equals("type")) {
                    token = tokenizer.nextToken();
                    while (tokenizer.hasMoreTokens() &&
                            (token.equals(" ") || token.equals("\t") || token.equals("=")))
                        token = tokenizer.nextToken();
                    type = token.substring(1, token.length() - 1);

                } else if (name.equals("href")) {
                    token = tokenizer.nextToken();
                    while (tokenizer.hasMoreTokens() &&
                            (token.equals(" ") || token.equals("\t") || token.equals("=")))
                        token = tokenizer.nextToken();
                    href = token;
                    if (tokenizer.hasMoreTokens()) {
                        token = tokenizer.nextToken();
                        // If the href value has parameters to be passed to a
                        // servlet(something like "foobar?id=12..."),
                        // we want to make sure we get them added to
                        // the href value. Without this check, we would move on
                        // to try to process another attribute and that would be
                        // wrong.
                        // We need to set lookedAhead here to flag that we
                        // already have the next token.
                        while (token.equals("=") && tokenizer.hasMoreTokens()) {
                            href = href + token + tokenizer.nextToken();
                            if (tokenizer.hasMoreTokens()) {
                                token = tokenizer.nextToken();
                                lookedAhead = true;
                            } else {
                                break;
                            }
                        }
                    }
                    href = href.substring(1, href.length() - 1);
                    try {
                        // Add code to use a URIResolver. Patch from Dmitri Ilyin.
                        if (m_uriResolver != null) {
                            source = m_uriResolver.resolve(href, m_baseID);
                        } else {
                            href = SystemIDResolver.getAbsoluteURI(href, m_baseID);
                            source = new SAXSource(new InputSource(href));
                        }
                    } catch (TransformerException te) {
                        throw new org.xml.sax.SAXException(te);
                    }
                } else if (name.equals("title")) {
                    token = tokenizer.nextToken();
                    while (tokenizer.hasMoreTokens() &&
                            (token.equals(" ") || token.equals("\t") || token.equals("=")))
                        token = tokenizer.nextToken();
                    title = token.substring(1, token.length() - 1);
                } else if (name.equals("media")) {
                    token = tokenizer.nextToken();
                    while (tokenizer.hasMoreTokens() &&
                            (token.equals(" ") || token.equals("\t") || token.equals("=")))
                        token = tokenizer.nextToken();
                    media = token.substring(1, token.length() - 1);
                } else if (name.equals("charset")) {
                    token = tokenizer.nextToken();
                    while (tokenizer.hasMoreTokens() &&
                            (token.equals(" ") || token.equals("\t") || token.equals("=")))
                        token = tokenizer.nextToken();
                    charset = token.substring(1, token.length() - 1);
                } else if (name.equals("alternate")) {
                    token = tokenizer.nextToken();
                    while (tokenizer.hasMoreTokens() &&
                            (token.equals(" ") || token.equals("\t") || token.equals("=")))
                        token = tokenizer.nextToken();
                    alternate = token.substring(1, token.length()
                            - 1).equals("yes");
                }

            }

            if ((null != type)
                    && (type.equals("text/xsl") || type.equals("text/xml") || type.equals("application/xml+xslt"))
                    && (null != href)) {
                if (null != m_media) {
                    if (null != media) {
                        if (!media.equals(m_media))
                            return;
                    } else
                        return;
                }

                if (null != m_charset) {
                    if (null != charset) {
                        if (!charset.equals(m_charset))
                            return;
                    } else
                        return;
                }

                if (null != m_title) {
                    if (null != title) {
                        if (!title.equals(m_title))
                            return;
                    } else
                        return;
                }

                m_stylesheets.addElement(source);
            }
        }
    }


    /**
     * The spec notes that "The xml-stylesheet processing instruction is allowed only in the prolog of an XML document.",
     * so, at least for right now, I'm going to go ahead an throw a TransformerException
     * in order to stop the parse.
     *
     * @param namespaceURI The Namespace URI, or an empty string.
     * @param localName    The local name (without prefix), or empty string if not namespace processing.
     * @param qName        The qualified name (with prefix).
     * @param atts         The specified or defaulted attributes.
     * @throws StopParseException since there can be no valid xml-stylesheet processing
     *                            instructions past the first element.
     */
    public void startElement(
            String namespaceURI, String localName, String qName, Attributes atts)
            throws org.xml.sax.SAXException {
        throw new StopParseException();
    }

    /**
     * Added additional getter and setter methods for the Base Id
     * to fix bugzilla bug 24187
     */
    public void setBaseId(String baseId) {
        m_baseID = baseId;

    }

    public String getBaseId() {
        return m_baseID;
    }

}
